Leaf and stem seedling rust resistance in wheat cultivars grown in Croatia

Diseases caused by Puccinia species can have devastating effects on wheat and other crops, causing severe economic losses by reducing grain yield and quality. Generally, three strategies are used to control leaf and stem rust wheat diseases: (i) incorporating genetic resistance into new cultivars (ii) the use of fungicides (iii) crop management. The first approach is the most environmentally and economically efficient. Combined with traditional selection techniques, marker-assisted selection (MAS) has become a valuable tool in selection of individuals carrying genes that control traits of interest, such as disease resistance. The objective of this study is to postulate leaf and stem rust resistance genes in 50 mostly Croatian wheat cultivars. Most of the cultivars were screened for the first time for rust diseases. The studies detected six leaf rust resistance genes (Lr2a, Lr3, Lr10, Lr14a, Lr17 and Lr26) and four stem leaf resistance genes (Sr8a, Sr31, Sr36 and Sr38). Nine wheat cultivars had one or more unidentified Lr genes that were not included in the set of 24 isolines, and six wheat cultivars had one or more unidentifed Sr genes. Knowledge on the identity of the seedling rust resistance genes in released cultivars and germplasm is essential for the incorporation of effective resistance genes into breeding programs to maintain a diversity of resistance genes in commonly grown cultivars.